1. Field of the Invention
This invention relates to methods and apparatus for automatically combining chemical components and synthesizing compounds therefrom, and more particularly to methods and apparatus for mounting and discharging pipette tips in such apparatus.
2. Background and Related Art
Contemporary chemical research that is designed to create new and useful compounds for pharmaceutical applications no longer relies on the inspired chemist who employed knowledge, experience, and intuition to select the chemical components to be combined. The modern systems that are used to synthesize experimental compounds employ robotic equipment that is programmed to attempt all possible combinations and leave the selection process to be applied to the end results. By maximizing the number of chemical combinations attempted, more compounds are evaluated, and the chance of success becomes greater.
A robotic laboratory chemical processor that performs the described programmed robotic chemical compounding is supplied by TECAN(copyright) U.S., Post Office Box 13953, Research Triangle Park, North Carolina 27709, and is identified as the xe2x80x9cGENESIS(copyright)xe2x80x9d sample processor. The GENESIS(copyright) sample processor is able to automatically mount a set of up to eight molded, rack-mounted pipette tips onto nozzles that are each connected to a controlled aspiration-injection unit. The GENESIS(copyright) sample processor moves the pipette tips in a manner to transfer a measured quantity of a chemical component from a reservoir in a first position to a reaction site in a second position where they are combined with other components. The chemical combination is warmed and agitated according to a prescribed program to attempt to encourage a reaction between the components. The molded pipette tips are typically used only once and discarded in order to minimize the chance of cross contamination of the chemicals.
While it is important to discard used pipette tips to avoid contamination of one chemical to another, this practice is expensive and wasteful of materials. The molded pipette tips that are typically used are expensive when used in large numbers. Pipette tips are expensive because they are injection molded and they occupy a substantial amount of space. Thus, substitution of a simpler, more economical component for the known molded pipette tip could generate savings in money and materials. In addition, since the prior art molded pipette tips are fed to the robotic apparatus in a rack that requires space to store and regular refilling with pipette tips, other forms of pipette tip material, as disclosed below, provide further economy by eliminating the rack refilling operation. A form of pipette that is recognized by the present invention to be economical and effective for use in a robotic chemical sample processor is a pipette tube, i.e., a hollow cylindrical member with two open ends.
It is therefore an object of the present invention to provide pre-cut pipette tubes that can acquire a very small sample quantity and are able to be automatically mounted to pipette aspiration nozzles for use in a chemical sample processor.
It is a further object of the present invention to provide an apparatus to convey and mount the pre-cut pipette tubes of the invention to aspiration nozzles of a robotic sample chemical processor.
It is an additional object of the present invention to provide chemical sample processor pre-cut pipette tubes that are able to fit snugly into pipette engagement rings for use in a chemical sample processor.
These and other objects of the present invention will be better understood through the description and claims to follow.
The present invention provides an apparatus and method for chemical processing, comprising apparatus for conveying pre-cut pipette tubes to a position under a set of aspiration tubes and means for mounting the pipette tubes to the aspiration tubes in an automated chemical sample processor. In particular, the pre-cut pipette tubes are stored in a magazine hopper and dispensed to a transporter adapted for receiving and transporting individual pipette tubes. The transporter positions the pipette tubes for engagement by the aspiration tubes. Upon completing the sequence of steps for combining chemical components, the invention apparatus discharges the used disposable pipette tubes and is ready to begin a second cycle.